Air-heater for aeronautical motors.



c. B} KIRKH'AM.

AIR HEATER FOR AERONAQHCAL MOTORS. APPLICATION FILED SEPLZT. 1916.

1,326,405, Patented Dec. 30,1919.

2 SHEETS-SHEET 1- vweufoz CHARLESBKIRKH M c. B. KIRKHAM. AIR HEATER FORAERONAUT'ICAL MOTORS.

APPLICATION FILED SEPT, 27

Patented Dec. 30, 1919.

2 SHEETSP-SHEET 2.

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CHARLES B. KIRKHAM, OF BUFFALO, NEW YORK, ASSIGNOR ".lIO CURTISSAEROPLANE AND MOTOR CORPORATION, A CORPORATION OF NEW YORK.

AIR-HEATER FOR AERONAUTICAL MOTORS.

To all whom it may concern:

Be it known that 1, CHARLES B. KIRKHAM, a citizen of the United States,residing at Buffalo, in the county of Erie and State of New York, haveinvented certain new and useful Improvements in Air-Heaters forAeronautical Motors, of which the following is a specification.

My invention relates to internal combustion engines and has specialreference to an improved substantially streamline form of heaterintended for use upon aeronautical motors of the multi-cylinder type.

For continuous operation of an aeronautical motor at high speed,especially during the winter months when the surrounding air is ata'very low temperature and at high altitudes, it is essential that thecontinuity of the fuel supply to the engine cylinders be uninterruptedso long as the air craft is in flight. Condensation of the fuel gasesunder the conditions specified, if a preventive is not installed, isresponsible more than anything else for motor stoppage and the dangerresultin therefrom 'to both the aviator and the mac ine. Continuousmotor operation is best obtained by the admission of preheated air tothe carburetion sys-' tem and it is to this end, i. 6., the productionof an essentially novel, substantially streamline air heater that thepresent invention is designed.

In practice, I contemplate the utilization of two heater jackets of aconstruction intended for positive and cooperative association with theseveral horizontally alined exhaust conduits characteristic of theCurtiss V-type motor. By the provision of a separate heater for theexhaust conduits of each bank of engine cylinders, it is possible tomaintain perfect symmetry (essential to aircraft construction) and atthe same time provide for the ample supply of preheated air to the motorcarbureters, of which, in the present instance, there are two-one foreach bank of cylinders. To amplify the air supply to the dual carburetersystem and to insure a positive induction of air at a speed forced bythe air rush incident to flight, it is proposed to provide an opening inand at the forward end of each heater jacket. The several exhaustconduits pierce the heater jackets in alined relation and to a certainextent break or deflect the air rush Specification of Letters Patent.

Patented Dec. 30, 1919.

Application filed September 27, 1916. Serial No. 122,487.

to accordingly augment the heating influence offered upon the airprior.to its admission to the carburetors. The aft end of each heateracket is closed in conical form and the air confined to the opposedjackets thus caused to seek an outlet provided therefor-open to thecarburetion system. Various details of construction are also con siderednovel and will be therefore specifically disclosed hereinafter.

For a detailed description of the invention, reference should be had tothe accompanying drawings wherein like characters of reference designatelike or corresponding parts throughout the several views, of which:

Figure 1 is a fragmentary side elevation of a tractor aeroplane equippedwith a Curtiss V-type motor that the application of the invention may beadvantageously shown;

Fig. 2 is a front end elevation of the aeroplane and equipmentillustrated in Fig. l, and

Fig. 3 is. an enlarged transverse section .of the heated jacketillustrating the manner in which the exhaust conduits pass therethrough.a

In the embodiment of the invention selected for illustration, 1Odesignates the forward end of the fuselage or bod por 'on of a tractoraeroplane equippe wit a standard Curtiss V-type aeronautical motor. Thecylinders of the motor are designated 11 and arranged in banks atopposite sides of the fore and aft axis of the machine,

each cylinder extending without the fuselage or body portion 10.

The exhaust conduits 12 lead from the exhaust ports of the motor inseries, the conduits of each series extendin in horizontally alinedrelation. In an eight-cylinder motor of the type illustrated, there arefour exhaust conduits located at each side of the machine.

It is customary at the present time to equip a multi-cylinder V-typemotor with a dual carbureter system that the fuel supply to the severalcylinders may be ample and continuous. The carburetor system hereinillustrated is designated in its entirety by the numeral 13. Theprovision of the dual carbureter system 13 makes it advantageous toprovide a dual air heater system, not only to gain symmetry but toprovide for the ample induction of heated air to the engine cylinders.

Each series of conduits 12 acts as a support for its associated heaterjacket 14, the heater jacket, in each instance, having a greaterdiameter than the diameter of the conduits 12. As illustrated'toadvantage in Fig. 1, the several conduits pierce or penetrate thejackets 14 to terminate therebeyond, and, being of smaller diameter,afford an air passage Way interiorly of the heater jacket above andbelow the conduits piercing therethrough. In view of such anarrangement, the air flow interiorly of each heater jacket is somewhatbaflied and appreciably broken to accordingly augment the resultingheating influence thereon.

In form, each heater jacket or grid is of a substantially streamlineformation having a frusto-conical forward terminal 15 and a trul conicalaft terminal 16. An opening 17 is ormed in each heater jacket at itsforward end to insure a forced induction of air proportionate to the airrush incident to flight. Such an arrangement is conducive to the maximumair supply during flight at high speed and a relatively decreased supplyas the speed of the machine is reduced. The aft end ofeachjacket beingclosed, the

air confined therein is caused to seek an out- 1 let which, for reasonshereinafter explained,

I locate adjacent the rear end of the jacket, preferably equidistantfrom the rear spaced conduits 12. An outlet pipe extension 18 is formed11 the heater jacket at each side of the motor for fitting engagementwith one end of an associate flexible carbu:

reter air supply pipe 19,0f which in the embodiment shown, there aretwo, located respectively at opposite sides of the fuselage toextendthereinto at a point in proximity to each heater jacket and asillustrated in Fig. 2. By thus inclosing the carbureter air supply pipes19, the head resistance during flight is appreciably reduced.

duce the head resistance by reason of the fact that the major portion ofeach exhaust conduit is embraced or inclosed by one or the other of thestreamlined jackets and ac given a substantially streamline form. achconduit 12 extends but a little beyond its inclosing jacket,-c'. 6.,only sufficient to conduct the, spent gases to the 0 en atmosphere. Topreclude the formation of a retarding force, the conduits are each of aspecialend formation, preferably beveled as indicated at 20 in Fig. 1.

The fastening means for each heater jacket may be described ascomprising a clip 21 of a'right-angle formation designed for rivetedfastening as indicated at 22 to the heater jacket and bolted fasteningas indicated at 23 to the conduit 12. Each jacket 14, at thediametrically opposed openmgs formed therein through which the conduits12 extend, is outwardly flanged as indicated at 24, the flangeencircling the conforce of the carbureter system occasioned by movementof the engine pistons, admitted to the carbureter system for ultimatedistribution tothe engine cylinders in a preheated state. Condensationof the fuel gases in winter, at high altitudes and under allcircumstances is thus effectually prevented.

The very compactness of an aeronautical motor while essentially andcertainly advantageous in many respects necessarily brings at least oneof the valve operating springs into such proximity to the exhaustconduits 12 as to offer thereon a deterioratingeiiect. The heat from theexhaust during high speed operation of the motor is intense and unlesssome means he provided Y whereby the adjacent valve operating springsare protected, the spring metal will eventually softeifij decrease inresiliency and finallyfail to function in properly controlling operationof its associate valve mechanisin. The springs thus affected are hereindenoted 25. To obviate the foregoin contingency and to deflect the heatof t e exhaust, I interpose between the conduits 12 and the severalsprings 25 a shield 26 of appropriate design. The shield, as illustratedto advantage in Fig. 3, ma be made as an integral part of the conduit 12or if desired fastened thereto or to the engine cylinder.

While in the foregoing I have illustrated one preferred embodiment ofthe invention, I desire it to be understood that the exhaust conduitsmay be set at a rearward inclination, the heater jacket changed ingeneral conformation and the type of shield interchanged should occasiondemand. Further, I do not intend thatthe device of the invention shallbe limited in its use to a Ourtiss V-type motor, for it is apparent inits inception that the nature of the invention is such as to warrantunrestricted utility and application in connection With motors varyinggreatly in type. Specifically, I desire to be limited on y in so far asthe scope of the subjoined claims must warrant.

What is claimed is:

1. In an aircraft, an internal combustion motor having exhaust conduitsin bank,an

air heater casing of substantially uniform dimensions throughout andstreamlined at its ends, said casing enveloping said conduits and havingan ingress opening facing in the direction of travel of the aircraft,and an.

egress opening connected with the motor, and means for securing saidcasing to said bank of conduits' 2. The combination with an aircraft,the

internal combustion engine therefor and the large portion thereof ofsubstantially uni form dimensions throughout, said casing also having anopening facing in the duct:-

tion of travel of the aircraft and an egress opening connected with themotor, and

means securing said air heater case to said conduits.

3. The combination with an internal combustion en no and the exhaustpipes therefor, of a su stantially streamlined air heater having an opensubstantially frusto-conical forward end and a closed substantiallyconicalrear end, and a conduit leading from the heater to the motor.

4. In an aircraft, an internal combustion motor, exhaust conduitstherefor which proj ect without the body of the craft, a substantiallystreamlined air heater jacket of an elongated cylindrical shape incasingsaid exhaust conduits and having its extreme forward end open to theatmosphere, and an air conduit connecting the rear end of said casingwith the motor, and means securely fastening said cylindrical casing tosaid exhaust conduit.

5. The combination with an internal com bustion motor and the exhaustconduits therefor, of an air heating system comprising an air heatingjacket partially surroundin said exhaust conduits, said heater jacketbeing of an elongated cylindrical shape and having its ends streamlinedsaid jacket also having an opening facing in the direction of travel ofthe aircraft, and a means to convey heated air from the heater jacket tothe cylinders of the engine, and means securely fastening saidcylindrical casing to i said exhaust conduits. I

6. In an air craft, an internal combus tion motor. the exhaust conduitstherefor, a substantially streamlined air heater jacket of cylindricalshape having rows of longitudinally spaced apertures on opposite sidesof said jacket through which said conduits pass, and an integral flangearound each of the exhaust conduit apertures to make a tight fit betweenthe conduits and ,the heater jacket, and means securing said flanges tothe"exhaust conduits.

In testimony whereof I afiix my signature.

CHARLES B. KIRKHAM.

